The Mekong delta is the southernmost region of Vietnam, with a population of approximately 20 million and a total area (excluding islands) of about 4 million hectares, of which about 2.60 million hectares are used for developing agriculture and aquaculture. The Mekong delta is particularly important for the overall development of the country. However, in recent years, under the impact of global warming, the Intergovernmental Panel on Climate Change has defined the Mekong delta as one of the three most vulnerable plains, due to climate change, sea level rise, and land subsidence. Especially, the impact of water resources exploitation of upper Mekong countries has been posing great challenges to the sustainable development of the region. Recognizing the nature and development trend of the Mekong delta, new threats and challenges that help to form scientific bases for development models and solutions for the region is very important. This article presents assessments on the challenges and strategic viewpoints in regard to sustainable development and adaptation to climate change of the Mekong delta.
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Introduction
Located in the southern-most part of the country, right next to Ho Chi Minh city (the second centre of political and lead economic development of the country), Mekong delta has a population of nearly 20 million (approximately one quarter of the country population); its agricultural production accounts for over 50% of the country’s total production while food export and fruit and fishery export amount to over 90% and 70% of the country respectively The development of the Mekong delta in the last decades (where agriculture is the mainstream occupation) is a miracle that has been recognized by international communities This
is also a brave base-region, its resilience marked by the nation’s historic victory on April 30th It can be said that the Mekong delta has confirmed its extremely important position in all aspects of economy, politics, society and national security and has received the trust of all the people
of the country
The Mekong delta has experienced the adverse impact of intense human and natural activities It is a new delta with diverse ecosystems and fertile soils However, much of the soil suffers from saline contamination and is heavily affected
by aluminum In addition, this area has been influenced adversely by climate change and the over-exploitation of water resources by upstream countries
However, no long-term investment strategy has been proposed for the Mekong delta, in its development planning; there has been no regional planning, with consideration
of technical, economic, social and ecological factors Meanwhile, we have planned for short-term periods or individual sectors We have not yet evaluated the full of challenges and opportunities of the region, nor created a breakthrough and positive change Therefore, it is urgent to have a sustainable development strategy for the delta, which
Basic trends and strategic viewpoints
for sustainable development in adaptation
to climate change in the Mekong delta
Dinh Hoa Tran *
Vietnam Academy for Water Resources
Received 25 December 2017; accepted 3 April 2018
*Email: tranhoa08@gmail.com
Abstract:
The Mekong delta is the southernmost region of
Vietnam, with a population of approximately 20
million and a total area (excluding islands) of about 4
million hectares, of which about 2.60 million hectares
are used for developing agriculture and aquaculture
The Mekong delta is particularly important for the
overall development of the country However, in
recent years, under the impact of global warming,
the Intergovernmental Panel on Climate Change has
defined the Mekong delta as one of the three most
vulnerable plains, due to climate change, sea level rise,
and land subsidence Especially, the impact of water
resources exploitation of upper Mekong countries
has been posing great challenges to the sustainable
development of the region Recognizing the nature and
development trend of the Mekong delta, new threats
and challenges that help to form scientific bases for
development models and solutions for the region is
very important This article presents assessments on
the challenges and strategic viewpoints in regard to
sustainable development and adaptation to climate
change of the Mekong delta.
Keywords: climate change, sustainable development,
water resources, water resources security.
Classification number: 6.2
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will not only substantially contribute to the development
of Vietnam, but also receive the special attention of
international community
Basic trends and viewpoints of challenges in the Mekong
delta
In recent years, the Mekong delta has been adversely
affected by climate change and the over-exploitation
of water resources by the upstream countries This has
considerably impacted the local people, as also development
and production activities in the region This poses great
challenges to the sustainable development of not only the
Mekong delta, but the country as a whole
A large number of studies have been carried out on the
Mekong delta by researchers and scientific institutes, for
identifying an optimal solution to the delta’s problems and
challenges However, there is still not the same point of
view between the solutions
Scientists and research organizations from both Vietnam
and foreign contries have put forth quite a few ideas and
viewpoints on the trends and impacts of these issues on
the life and development of the Mekong delta Research
results and viewpoints are very positive, with the desire to
help detect the true nature of the impact, in order to find
the optimal solution for the region However, there are still
some issues on which there has been no consensus, in terms
of assessment viewpoints So it requires a comprehensive
understanding of the mechanism of existing issues and challenges in the region
Land subsidence in the Mekong delta
Mekong delta was formed about 8,000 years from alluvial deposition Morphological evolution of the Mekong delta includes two primary processes, viz., alluvial deposition (during flood seasons) and natural subsidence (a continuous slow process lasting centuries) [1] Currently, a decrease in fluvial sediment supply and widespread over-exploitation of the groundwater and sand have resulted in enhancing subsidence through aquifer compaction (Fig
1) It is important to note that people are not aware of the land subsidence, as the process is normally slow and hidden from morphological changes, due to deposition or erosion
In fact, as many major river deltas in the world such as Mississippi (USA), Colorado (USA), Yellow river (China)…
[3], due to the combined effect of natural subsidence, global sea-level rise and reduced alluvial deposition, the Mekong delta has become vulnerable to inundation Recently, in the Mississippi river delta, where tens of hydropower dams have been constructed along the 3,734 km of Mississippi river bank, through 10 states From 1932 to 2010, in the coastal areas of Louisiana and Mississippi, river deltas have been flooded, with a total affected area of 5,000 km2 (Fig
2), which is equivalent to half the area of the southern Ca Mau peninsula
Fig 1 The rate of lowering of the groundwater table (left) and surface subsidence of the Mekong delta (right) [2]
In fact, as many major river deltas in the world such as Mississippi (USA), Colorado (USA), Yellow river (China)… [3], due to the combined effect of natural subsidence, global sea-level rise and reduced alluvial deposition, the Mekong delta has become vulnerable to inundation Recently, in the Mississippi river delta, where tens of hydropower dams have been constructed along the 3,734 km of Mississippi river bank, through 10 states From 1932 to 2010, in the coastal areas of Louisiana and Mississippi, river deltas have been flooded, with a total affected area
peninsula
Fig 2 Natural subsidence in coastal areas in Louisiana and Mississippi river deltas (black dots are observation locations) [4]
From the realities facing us in the major deltas of the world with conditions similar to those of the Mekong delta, it has been found that natural land subsidence
in the deltas is a clear and irreversible trend Groundwater over-exploitation is one
of the primary factors responsible for the increasing subsidence in the Mekong river delta Therefore, it is necessary to have properly observation, management, and analysis In other words, a comprehensive survey should be conducted for formulating proper solutions
Fig 1 The rate of lowering of the groundwater table (left) and surface subsidence of the Mekong delta (right) [2].
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From the realities facing us in the major deltas of the
world with conditions similar to those of the Mekong
delta, it has been found that natural land subsidence in the
deltas is a clear and irreversible trend Groundwater
over-exploitation is one of the primary factors responsible for the
increasing subsidence in the Mekong river delta Therefore,
it is necessary to have properly observation, management,
and analysis In other words, a comprehensive survey should
be conducted for formulating proper solutions
River and coastal erosion
Beside the natural changes, overexploitation and operations from human activities in the upstream countries and the Mekong delta have resulted in raising the challenges
to the Mekong delta Climate change will have considerable impact on the delta such as flow regime changes,
sea-3
subsidence of the Mekong delta (right) [2]
In fact, as many major river deltas in the world such as Mississippi (USA), Colorado (USA), Yellow river (China)… [3], due to the combined effect of natural subsidence, global sea-level rise and reduced alluvial deposition, the Mekong delta has become vulnerable to inundation Recently, in the Mississippi river delta, where tens of hydropower dams have been constructed along the 3,734 km of Mississippi river bank, through 10 states From 1932 to 2010, in the coastal areas of Louisiana and Mississippi, river deltas have been flooded, with a total affected area
peninsula
Fig 2 Natural subsidence in coastal areas in Louisiana and Mississippi river deltas (black dots are observation locations) [4]
From the realities facing us in the major deltas of the world with conditions similar to those of the Mekong delta, it has been found that natural land subsidence
in the deltas is a clear and irreversible trend Groundwater over-exploitation is one
of the primary factors responsible for the increasing subsidence in the Mekong river delta Therefore, it is necessary to have properly observation, management, and analysis In other words, a comprehensive survey should be conducted for formulating proper solutions
EAST SEA
A
Fig 2 Natural subsidence in coastal areas in Louisiana and Mississippi river deltas (black dots are observation locations) [4].
Fig 3 Inundation map of the Mekong delta projected according to climate change scenario and sea level rise [5].
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level rise which causes increased inundation hazard (Fig
3) and severe erosion in coastal areas [5] In addition, the
operation and over-exploitation of water resources in the
reservoirs have resulted in changing of bankfull discharge
and decreasing of alluvial deposition, which causes
increased erosion in rivers, channels, and coastal areas
Thus, downstream rivers and coastal deposition locations
are generally unstable, as per inherent nature
The recovery of eroded coastal areas due to natural cycles
is infeasible; maintaining the sustainability and reduction of
eroded locations appears unrealistic, as the capability for
controlling these locations has been eroded The trend of
river and coastal erosion is increasing and is unavoidable, in
view of the natural condition and exploitation of water, both
by domestic sources and by other upstream countries of the
Mekong delta For example, the volume of sand exploitated
is in exceess of the fluvial sediment supply Therefore,
using non-structural or structural strategies to restore the
eroded bank to its original condition is infeasible In the Red River delta, the river bed has been declining gradually after hydroelectric power dams were built upstream For example, in Hai Hau beach - Nam Dinh province, one of the famous Churches has collapsed due to beach erosion These phenomena are also found in coastal areas of large-scale river basins around the world America has recently been studying solutions for partial sediment restoration in the coastal areas of Louisiana and Mississippi river deltas (Fig 4)
Therefore, in order to protect the land, we need to find solutions and accept the lowering of the river bed and elevation of coastal plains It is easy to recognize that the Mekong delta is unified and has inter-connected canal systems, due to which any changes in a local area will affect the whole system Any solutions proposed to protect the river and coastal banks should be considered carefully, to avoid other unwanted effects
Fig 4 Pilot project to transfer sediment from the river to plains [6].
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Degradation of water resources
Till the time of this report, the total volume of the flows
to the Mekong delta have not decreased significantly The
reduction of the total flow volume will become severe, when
all the proposed upstream works have been completed In
particular, if the regulation works on the Tonle Sap river
for flood protection and rising water level in the Tonle Sap
purposes, as well as oil and gas exploitation, and projects
of Thailand, Laos, Cambodia to lift water from the Mekong
river for agricultural development (covering an estimated
total area of more than 1.8 hectares) are implemented, it will
lead to extreme conditions of flood and drought flows [7]
The impacts from exploitation of water resources projects
upstream are not only reducing the quantity of water, but
also its quality, causing reduction of organic elements
in water Further, the pollutant water from pesticides,
posing a grave threat to biodiversity, yield, and quality of
fisheries, will be a great challenge for the Mekong delta
Along with that, the pollution from waste water and sewage
from aquaculture are getting worse Although the coastal
zone in the Mekong delta is conducive for aquaculture
and biodiversity, production is unstable due to the frequent
occurrence of epidemics These effects are more severe than
the lack of water
Viewpoint on renovation and sustainable development in
the Mekong delta
In the context of international integration, local
and regional levels across the country having strategic
development based on the strength of each region,
there is essential to recognise advantages and minimise
shortcomings in order to maximise the available resources
By analyzing and identifying the challenges for the Mekong
delta as described above, sustainable development of the
delta must be harmonised with three core elements: “Land
- Water - People” The development history of Vietnam is
always associated with “Water” Especially the Mekong
delta, the development of the region over the past 300
years was always associated with the way which people
behaved, vis-a-vis the relationship between “Land” and
“Water” With relatively flat terrain characteristics, an
inter-connected canal system and similarity in culture pervading
the whole region, it can be said that the Mekong delta is
a unified form and has a great interaction with each other
Therefore, Mekong delta needs to have regional linkages,
highly systematic activities that bring more efficiency in
economic development as well as in adaptation to climate
change and other factors
Placing the Mekong delta in the context of water
degradation in terms of quantity, quality, and suspended particles, and increasing environmental pollution, it is very likely that development orientation for the Mekong delta
will have to “Concentrate on the large-scale agricultural
production of high quality and productivity; combining services, ecotourism and appropriate industry” It is time to
change the “traditional food security” strategy of the recent decades into “high-quality food security”, by promoting
high-value and export-oriented products and looking into large-scale and professional production models
Conclusions
It can be concluded that a key issue for strategic orientation transformation of the Mekong Delta is the drastic restructuring of its agricultural sector, including: (i) Reorganizing and redistributing land use and farming practices in respect of the decreasing rice cultivation and the number of crops; (ii) Increasing the area of aquaculture; (iii) Increasing the area of fruit trees; (iv) Promoting and using land for ecotourism; (v) Increasing the area of mangroves; and (vi) Re-planning the whole system of irrigation works with respect to ecological areas: fresh water, salt water, and brackish water
All these strategies will not only enhance local standards
of living, but also ensure harmony and conformity with the
laws of nature In other words, “challenges” can be turned into “opportunities” for development.
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